Boiler



Dec. 3, 1929. B. B. WHITTAM I 1,737,988

BOILER Filed March 29, 1927 ATTORN EY5 Patented Dec. 3, 1929 UNETED STATES PATENT OFFEE BENJAMIN B. WHITTAM, OF ELIZABETH, NEW JERSEY, ASSIGNOR TO THE BABCOCK & WILCOX COMPANY, OF BAYONNE, NEW JERSEY, A CORPORATION OF NEW JERSEY BOILER .Application filed March 29, 1927. Serial No. 179,232.

My present invention relates to seamless drums for boilers and to manholes and covers for the same, and comprehends a method of mounting an integral cover within the drum.

My invention will be best understood from the following description taken in connection with the accompanying drawings showing embodiments thereof. In the drawings, Fig. 1 is an elevation. of a drum showing in dotted lines the mounting of a cover within the drum; Fig. 2 is a section on the line 2-2 of Fig. 1; Fig. 3 is a partial longitudinal cross section through a drum on the line 3-3 of Fig. l; Fig. 4 is an end view of the drum of Fig. 3; Fig. 5 is a partial cross section on the line 5-5 of Fig. 6 and shows a modified structure, and Fig. 6 is an end view of the drum of Fig. 5.

Like reference characters indicate like parts in the several views.

In the illustrative embodiment, a seamless drum A has a circular manhole cover B closing one of the manholes 10 from within the drum. This cover is mounted on a suitable hinge structure 11 secured to the interior wall of the drum. The cover B is fixed to the end of the drum by standing bolts 12 extending from the cover and engaging one or more bars 13 spanning the outer end of the manhole 10.

In my present invention, the drum may be constructed in the way described in application Serial No. 184,513, filed September 9, 1926, except that one or both of the end holes is to be finished larger thanthe manhole required. The holes are machine dressed and finished to the eXact desired size and in any well-known manner. At least one of the holes is made large enough to fit a bushing or frame for the cover, the bushing forming the manhole 10. One or more covers B are prepared and made of a diameter to enter the large hole thus prepared to fit the bushing. This is so that the cover may be inserted through the machined opening in the shell and be placed within the drum.

The bushing must have a machined fit both with the hole in the drum A and with the flange of the cover B. The complete bushing forms the inner cylindrical surface of the finished manhole 10. I prepare the bushing in parts or sections because it will have an exterior diameter greater than the hole in the drum. These sections are each conveniently inserted within the drum. They are then placed against the inner bearing surface from within the drum and formed into a unitary bushing or frame. v r

I show in Figs. 3 and 4 a construction in which the bushing comprises two equivalent or line parts15. The inner extremity of each part has an outer semi-cylindrical surface ending in a tapered frusto-conical exterior surface15 which extends to the end of the drum. The conical surface 15 fits the interior of the hole within the shell and transfers the pressures from the cover to the drum. The manhole opening 10 is cylindrical and ends in an interior ledge 15 against which a flange of the cover will be seated. The halves 15 have longitudinal meeting surfaces sloped from a meeting peripheral edge toward the axis of the cylindrical manhole 10. This construction results in slots 16 located diametrically opposite one another when the two halves 15 are fitted into place. These two slots are filled With a welding substance to make the two halves 15'into an integral or one-piecebushing or frame. The ring is welded to the drum by adding a welding substance circumferentially to the s ace 19.

In Figs. 5 and 6, the two hal sections 17 of a bushing or frame each has an inner ledge 17 to seat the cover B. An outer ledge or square shoulder 17 transfers the thrust of the cover from the bushing into the body of the drum. Since the other surfaces of the bushing are cylindrical, they can transfer no load from the cover to the drum shell and there is not much tendency to expand the drum. The meeting surfaces of the two halves 17 are sloped from one another toward the manhole 10 as noted in connection with the frame 15. These sloped surfaces form slots 18 when the frame is assembled. The slots are filled with a welding substance to form the integral frame. Similarly, as with the form of Figs. 8 and 4, the ring is welded to the drum by the addition of a welding substance in the space 20.

The longitudinal meeting surfaces of the ring sections of the bushing may, if desired, be sloped in the opposite direction. This will permit welding the bushing to the drum at the same time that it is welded into a unit.

In construction, the finished circular cover is passed through the finished hole of the drum to rest within the drum. The parts of the sectional bushing or frame are then inserted through the same hole and fitted from within the drum into place, forming the manhole. The bushing may then be temporarily secured to the finished seat in the drum shell while the welding substance is added to the slots to unite the bushing together and unite it with the drum. This welding step may be thermit welding, electric welding, or the like. After the welding operation, the bearing ledge 15 or 17 may be trimmed and the excess metal ma be removed from the manhole. The circu ar cover may then be mounted in place and hingedly secured to the interior wall of the drum.

-It will be apparent that my invention pro vides a simple, expeditious means for and method of mounting a circular or approximately circular manhole cover within a seamless drum. This method is particularly advantageous where the drum is so short that the covers cannot be inserted withinv the shell without being injured by the heat used in closing in the second'end. This bushing and the method of its assembly will need to be applied to but one hole of a drum.

Various other methods maybe used to secure the bushing to the drum. For instance, the ring frame may be bolted to or be threaded into the drum and be within the scope of my invention. v

I claim: p

1. A method of mounting a manhole cover within a drum, including the steps of inserting the cover through an opening into the drum, inserting parts of a sectional manhole bushing within the drum, assembling said parts in place to form a bushing, and uniting the parts into an integral bushing.

2. A method of mounting a manhole cover Within a drum, including the steps of inserting the cover through an opening into the drum, inserting parts of a sectional manhole bushing within the drum, assembling said parts in place forming the manhole, and welding the parts into an integral bushing.

3. A method of mounting a manhole cover within a drum, including the steps of inserting the cover through an opening into the drum, inserting parts of a sectional manhole bushing within the drum, assembling said parts in place forming the manhole, and welding the parts into an integralbushing by a welding operation including the addition of a welding substance.

at. A method of mounting a manhole cover within a drum, including the steps of forming a manhole bushing in sections and making a cover therefor, preparing an opening in a drum to fit said bushing, inserting the cover within the drum and through the opening thereof, inserting the sections of said bushing through said opening into said drum, assembling said sections in place fitting the opening in the drum, welding the sections into an integral manhole bushing, and mounting the cover in position.

5. A method of mounting a manhole cover within a drum, including the steps of forming a manhole bushing in sections and making a cover therefor, preparing an opening in a drum to fit said bushing, inserting the cover within the drum and through the opening thereof, inserting the sections of said bushing through said opening into said drum, assembling said sections in place fitting the opening in the drum, welding the sections into an integral manhole bushing, welding the bushing to the drum, and mounting the cover in position.

6'. A method of mounting a manhole cover within a drum, including the steps of forming a manhole bushing in sections and making a cover therefor, preparing an opening in a drum to fit said bushing, inserting the cover within the drum and throughthe opening thereof, inserting the sections of said bushing through said opening into said drum, assembling said sections in place fitting the opening in the drum, Welding the sections into an integral manhole bushing by a welding operation including the addition of a welding substance, and mounting the cover in position.

7; A method of mounting a circular manhole cover Within a drum, including the steps of forming a manhole bushing in sections and making a cover therefor, preparing an opening in a drum to fit said bushing, inserting the cover within the drum and through the opening thereof, inserting the sections of said bushing through said opening into said drum, assembling said sections in place fitting the opening in the drum,

welding the sections into an integral manhole bushing and welding the bushing to the drum by welding operations including the addition of a Welding substance, and mounting the cover in position.

8. A bushing for lining a manhole in a drum consisting of parts arranged to fit a hole in the drum and provided with meeting surfaces arranged to diverge inwardly from one another to permit welding of the frame into a unitary structure by the addition of a welding substance, said parts being united together and welded to the drum.

9. A section of a bushing for lining a manhole having an outer surface adapted to transfer pressure to the boiler drum, an inner cylindrical surface adapted to form a portion of a manhole, said surfaces, being joined by a longitudinal surface diverging from a plane radial to the cylindrical surface whereby the sections of the bushing, when assembled, have meeting surfaces diverging from one another.

10. In combination, a seamless drum having a substantially circular hole therein, a

bushing lining said hole and formed of sections secured together, and a cover contacting With the inner end of said bushing and closing said hole.

11. In combination, a seamless drum having a substantially circular hole therein, a bushing lining said hole and formed of sections Welded together and Welded to the drum, and a cover contacting with the inner end of said bushing and closing said hole.

BENJAMIN B. VVHITTAM. 

